Hoisting mechanism for dump trucks



` `19 1927. 1,624,977 Apr! J. E. REID ET A1.-

HoIsTING MECHANISM FOR DUMP TRUCKS Filed Sept. 12. 1923 5 Sheets-Sheet 1 April 19, 1927f J' E' REID ET AL I. 624 977 HOIASTING MEcHANfsM FOR DUMP TRUcKs Filed swt-,12. 1923 5 Sheets-Sheet 2 Q 6 yENT R5 MY M2M M7 ,d ATTORNE 5 April 19, 1927.

J. E. REID ET AL OISTING IIECHANISM FOR DUMP TRUCKS Filed Spt 12. 1923 s sheets-sheet s y 8, y La.

April 19, 1927.

1,624,977 J. E. man:- ET Al.

HOISTING MECHNISM FOR DUI!" TRUCKS Filed Sept. 12. '192s s sheets-sheet 4 pri. v-J.r='.1=2151|: ET A1.

vHOISTNG MCHANISM FOR DUMP TRUCKS.

Filed Sept- 12. 1923 5 Sheets-Sheet 5 TRS @L ey [M44] 1 a E; 7' Arrofmfrs Patented Apr. 19, 1927.

'Unirse stares JSIAH E. REED AND CE.

NATIGNAL MTR CGMPANY, GE' NEVI YORK, N. Y., A CORPORATION OF DELAW'ARE.

norsfr'ine inncnnnisu non DUMP manoirs.

Application filed September rlfhis invention relates to hoisting` mechanism for dump trucks and is concerned particularly with mechanism of a purely -mechanical characterfor this purpose, in con tradistinction to Vso-called hydraulicA hoist. lt has for its vgeneral object to provide construction which shall be rugged, simple, invariable Ain operation and operative through a power takeoff from the propelling engineof thcvehicleto which it is applied. More partioularly3 the invention is concerned with the mou nting of the operating parts on thepfranieby means which afford free angular movement of the, screw jacks during the tilting of the dump body as is necessary -for adaptation of the mechanism to this tilting without the imposition of'stresses on any of the elements. Further, the invention is concerned with the provision of `manually operable devices for connecting thek power to the hoisting mechanism for positive actuation thereof during the dumping and during the return of the body to position on the chassis. The invention is also concerned with the provision of an automatic throwout device whereby the power is automatically disconnected from the hoisting` mechanism4 at about the end of the predetermined travel of the dump ing` body in either direction. vStill another object of the invention is to provide a plurality of screw jacks which. are sorconnected to the body at opposite sides of the median line thereof as. to ,impress equal and uniform forces on the body for lifting itthereby eliminatinganytwisting stresses on the parts. A further object of the invention is to journal the operating jack shaft independently of the housing within .which its driving gears are disposed and to support the housing for saidl driving gears concentrically with but independently of said operating ja'clrA shaft. y Still another important feature of the invention has to do with the means forv fully lubricating the -parts at nall times, this object being realized in accordance with the improvements by wholly encasing the operating elements in an e11- closed housing within which an adequate supply of oi-l is maintained atall times. While it will be evident as! the ldescription proceeds `that the yprinciples involved.4 may be embodied in designs `of ydifferent forms from that l illustrated y herein, the Y. present embodiment shows the application of the 12, 1923. SerialvNO. 662,296.

invention to a chain drive` truck in which a single cradle is employed to support all of the hoisting mechanism and is trunnioned at opposite sides' in the side frame members by the screw when the body is elevated.

Figure 3 is a yfragmentary View in vplan on a larger scale of the manually operating devices for connecting the power Vto the hoisting mechanism and of the automatic throwout means associated therewith,

Figure el is a viewv in transverse section through the chassis shown in Figure 1 taken on the plane indicated by the line l-t of Figure 1 and looking in the direction of the arrows, parts of the housings being brolren away and some of the hoisting mecnanism being shown in section.

TFigure 5 isa view in section through the housing for one of the operating nuts and taken on ,the plane indicated vby the line 5- 5 of Figure 23 and looking in the direction of the arrows7 the tube for therpower shaft being broken away in the interest of clearness. i L

The invention .is notA concerned with the character of the dumping body-to Iwhich the improved hoist is applied. although it -is conteinplatedl that it shall be hinged on a vehicle chassis having side frame members a, a, and shall have its forward end moved upwardly therefrom for dumping.V Figure 1 indicates that vthe dumping body may be hinged at the rearend of the side frame members a, a', inthe journals a2. On the underside of the body may be secured a transverse rod `with which are engaged, preferably inv self-aligning relation, a plurality of screw jacks c, c', shown as two in number and disposed equidistant at opposite sides of the median line of the load so as to equalize hoisting stresses. The improved hoisting mechanismvto bev hereinafter ,1described is, in the,r illustratedembodiment, self-containedLin a manner,which isto'say that it is entirely supported on a cradle d Cil suspended transversely of the chassis and having at its sides trunnions rZ, cZg, journaled in brackets (Z3, fZ, which are secured to the chassis channels a., a. Normally, when the body rests on the chassis the cradle is suspended substantially vertically.

rThe improved hoist is ol' a wholly niechanical character comprising generally screw jacks c, c', formed as screw rods which are engaged by revoluble nuts (one of which is illustrated at c in engagement with the rod c) mounted within the cradle Z and rotated in one direction or another by a acl; shaft f which derives its rotatives movement through a shaft g driven from any available power take-od' such as a lay shaft Z1, from the vehicle transmission c'. Since the operating mechanism for each of the screw rods c, c', is the same it will be suflicient to describe that which is associated with the screw rod o as clearly illustrated in Figure 4l. The nut e is supported on a thrust bearing c and is formed with an external gear e2 with which meshes a gear splined as at f2 on the jack shaft f. The hub of the gear ,4 is extended to alford a suitable bearing for the shaft j" as will later appear. rl`he shaft 7 adjacent its mid-section has feathered thereon a sliding clutch gear Zt' which may be siid to the right or left for engagement with an internal gear Z formed within the face of a bevel gear Z or with an internal gear m formed in the face of a bevel gear m to secure transmission ofpower from one of these gears Z', m', to the jack shaft, and through it, rotation of the lifting nuts. Rotativo movement of the gears Z', m, is eliected through enga-gement therewith of a bevel pinion g" on the end of the power shaft g. Selective shifting of the compound clutch gear Z: may be brought about manually through a shifter fork n` carried on a shifter rod n journal-.ed slidably in the housing 0 for the operating gears described. rfhe shifter rod may be connected through a bell-crank irland linlr if with suitable hand operating means. By the construction described it will be evident that the direction of rotation of the jack shift is controlled by engaging the sliding clutch gear Ze with either the bevel gear Z or with the bevel gear m', since these two gears rotate simultaneously but in opposite directions. 'vVhen the parts are at rest, however, the clutch gear Zr: will be maintained in neutral position as shown in Figure ll.

The means for supporting and assembling the housings for the various moving parts of the hoisting mechanism will now be described, referring especially to the association of the housing for the screw rod c with the housing 0 for the operating gearing. The nut e is disposed within a casing p which has bolted thereto, to facilitate assembling, a cylinder p which is formed exteriorly as at p2 with an annular bearing surface on which is journaled the casing 0 by means of an annular flange carried at one side thereof and snugly embracing the bearing surface jf'. rllhe gear f which is formed with an elongated. hub is journaled within the cylinder p to facilitate its supfliort of the jack shaft j" which is splined therein. By this assen'ibly, the jaclr shaft 7" is jeurnaled only at its opposite ends and within the housings p, f7, for the respective screw jacks c, c, and has no bearing within the casing 0 for the power gears. rlhis greatly iacilitates machining and assembly and protects the parts against undue stresses such as miohtresult from misalignment. The housing o at its other side is similarly jeurnaled on the casing q for the rod c. The engagement between the casing 0 and the two housings p, g, permits relative angular movement therebetween so that while the casing o remains relatively lined on the chassis at all times the housings 2U, g, are free to swing angularly as the screw rods c, c, assume angular positions during the hoisting or lowering of' the body and the swinging of the cradle CZ.

T here has been described means by which power rom the shaft g may be applied to rotate the screw rods c, c', in either one direction or the other for the raising or lowering of the dump body. lt is desirable in devices of this hind, however, to provide for some automatic means for taking ofi' the power when the body has been raised or lowered through the predetermined distances since it is unsafe to rely on an operator to effect its disconnection at the proper time. To this end, the shifting rod it for the clutch gear 7c is extended through the housing 0 and engaged by a bell-crank i which is journaled on the housing o and is formed with an arm r adapted to be tripped by a suitably formed member g which may be carried with the housing g, when the housing q has oscillated through its intended path of travel during the raising or lowering of the body. For convenience, the member g may be bolted in between the housing (y and the flange g2 which carries the cylinder hereinbefore referred to. The invention is not to be limited to the precise outline of the tripping member g although as shown in Figure 5 it may have cam like portions which, when the housing g rocks come into engagement alternately with the arm r of the shifter bell-crank. The effect of this engagement is to slide the shifter rod n and disengage the clutch gear Z0 so that the body will come to rest in the position it then is in. lt will be eli'ective in its action whether the body be raised or lowered.

Another feature of the invention has to do with the oiling means which taken in conjunction with the enclosed housings for Srl keeping the operating parts free from dirt and foreign matter constitutes a very important practical part of the invention. As pointed out hereinbefore, it is intended that when the dumping body is at rest on the chassis the cradle (Z will assume a substantially vertical positicn. 'lhe screw rods c, c', extend downwardly within unbroken housings or wells formed. therefor and it is evident that a light oil may be poured into the upper part of the housings p, g, and virtually lill the casings within which the rods rest when the body is lowered. T aps t may be removed to drain these wells and permit changing of the lubricant. lubricant may also be introduced into the central casing for the drive gears. Since the body is lowered during the greater part of the time all of the parts will normally rest within a lubricant bath. Wvhen the body is raised the oil will lill the space normally occupied by the screw rods c, o, but will subsequently be displaced thereby when lowered. For the protection of these screw rods, in addition, extensible boots s of 'fabric or other suit-able construction may be associated with the housings y), g, aud with the screw rods so as to conform to their movements and encase them to exclude foreign particles.

As pointed out hereinbefore, changes in design may be made and some features of the invention covered by the appended claims will be found useful in other combinations than those disclosed herein.

What we claim is:

l. In a hoisting mechanism for dump bodies, brackets providing bearings fastened to the frame of the vehicle, a supporting frame with upwardly projecting end members provided with outwardly projecting stub shafts journaled in the bearings, a ack shaft journaled on the supporting` frame in the axis of the stub shafts, a power shaft gea-red operatively with the jack shaft and disposed in a plane including the axis of the stub shafts, means associated with the jack shaft for hoist-ing the body, and housings for the device.

2. Hoisting mechanism for dump bodies comprising screw jacks, revoluble nuts en gaged therewith, respectively, a jack shaft engaged operatively with the nuts to revolve them, a clutch gear splined centrally of the jack shaft, gears engageable selectively by the clutch gear to revolve the jack shaft in either direction, power means to drive said gears, separate housings for the nuts and a housing for the gears journaled on the tirs-t named housings and movable angularly with respect thereto.

3. Iloisting mechanism for dump bodies comprising screw jaclrs, revoluble nuts engaged therewith, respectively, a jack shaft engaged operatively with the nuts to revolve them, a clutch gear splined centrally of the jack shaft, gears engageable selectively by the clutch gear to revolve the jack shaft in either direction, power means to drive said gears, separate housing for the nuts and a housing for the gears journaled ou the first named housings and movable angularly with respect thereto, automatic means for disengaging the clutch and a member carried by one of said first named housings for actuating said automatic means.

4. Hoist-ing mechanism for dump bodies comprising screw jacks, revoluble nuts engaged therewith, respectively, a jack shaft engaged operatively with the nuts to revolve them, a clutch gear splined centrally of the jack shaft, gears engageable selectively by the clutch gear to revolve the jack shaft in either direction, power means to drive said gears, separate housings for the nuts and a housing for the gears journaled on the first named housings andv movable angularly with respect thereto, said first named housings including wells for said jacks for retaining a lubricant, extensible boots co-operating with the jacks to inclose their exposed portions, and means to drain the boots and wells.

This specification signed this 10 day of Sept. A. D. 1923.

JOSIAH E. REID. CHARLES L. NEIN. 

